Self-contained mechanical refrigerator



June 2, 1931.

R. W. DAVENPORT SELF CONTAINED MECHANICAL REFRIGERATOR Filed Aug. 5, 1926 INVENTOR. Ransom W. 04 venporf A TTORNE Y.

Patented June 2, 1931 UNITED STATES P ATENT. OFFICE RANSOM W. DAVENPORT, OF DETROIT, MICHIGAN, ASSIGNOR TO CHICAGO PNEUMATIC TOOL COMPANY, OF NEW YORK, N. Y., A CORPORATION; OF NEW JERSEY SELF-CONTAINED MECHANICAL REFRIGERATOR Application filed August 3, 1926. Serial No. 126,781.

This invention relates to the transforming .of heat by mechanical means and more specifically to self-contained outfits, usually in cabinet form, for producing refrigerating 5 effects. v

The combining of a refrigerating plant with a cabinet to form a self-contained mechanical refri erator is well known. Known types utilize or a working substancea lowboiling high-pressure liquid, such for enamle as sulphur dioxide or methyl chloride.

11 these refrigerators it .is common practice to combine the four principal elements, name- 1y, motor, compressor, condenser, and evaporator so that all may be removed as a unit in order that they may be put into or taken from the cabinet as a umt by the service man without the necessity of disconnecting any part containin the high pressure liquid, thereby to avoid t e well known dangers, delays and expense of servicing such apparatus on the users premises. It is obvious, however, that while the dangers attending the opening up of a high-pressure system in the users home are avoided by such means, compensating disadvantages result from the difiiculty of removing and transporting to the shop these great heavy plants comprising motors, pumps, condensers, evaporators, fans, switches, base plates, etc., and it is the more wastefulbecause in a very large percentage of the cases, probably ninety-nine out of a hundred, only the moving parts will actually be worked upon in the shop.

One object of the invention is to develop an improved ty e of self-contained refrigerating outfit. other object is to prov1 e apparatus from which the parts requiring servicing can be quickly and safely removed and easily transported without disturbing an parts not requirlng servicing. Another ob ect is to device an improved combination of cabinet and refrigerating plant permitting a novel arrangement of the apparatus arts and a complete segregation of the movmg parts from the non-moving parts. Other ob ects will be ap arent from the detailed description which ollows.

Instead of first combining into one plant 0 all or most of the mechanical, controlling, and

heat transforming elements and then combining this in turn with the cabinet as has previously been done in many ways, the present invention contemplates combining with the food cabinet the heat transferring elements comprising the condenser and the. evaporator which are built into the cabinet, so to speak, while the moving parts consisting essentially of a motor anda pump with necessary controls may form a separate unit. The condenser is preferably arranged to be air cooled but no fan or other mechanically driven air-agitating or other draft inducing means are provided. The connections between the pump or compressor and the evaporator and condenser are readily separable to permit the convenient substitution upon the premises of a new motor-pump. unit in case of failure of the old. Opening of the system can be effected without danger since the invention is designed to apply to systems utilizing as working substances harmless, lowpressure, high-boiling liquids operating in accordance with the process disclosed in my copending application, Serial No. 15,172, filed March 12, 1925. The invention further comprises suitable means for deflecting from the cabinet the heat given up by the condenser, and for protecting the condenser element against damage.

In order to illustrate the invention, one concrete embodiment thereof is shown in the accompanying drawings, in which:

Fig. 1 is a vertical sectional view of a refrigerating cabinet substantially on the line 11 of Fig. 2;

Fig. 2 is a rear end elevational view of the cabinet shown in Fig. 1.

Fig. 3 is a fragmentary sectional view on an enlarged scale substantially on the line 33 of Fig. 2.

The embodiment of the invention chosen for the purpose of illustration comprises a cabinet A of any suitable or desired type having walls insulated against the passage of heat which may be arranged for the preservation of perishable articles, the freezing of liquids, or both. Secured within the cabinet is an evaporator element 3, such as a coil of pipe disposed adjacent the cabinet wall.

Upon the exterior of the cabinet is disposed a condenser element 4. For convenience and to (permit short connections, the evaporator an condenser elements may be on o posite sides of the same wall of the box, suc as its 'back as indicated. A connection 5' leads from the bottom of the condenser to the bottom of evaporator 3, a suitable feeding device or expansion member 6 forming a part of the connection. A connection 7 indicated in part dia ammatically by a single line for the sake o clearness, leads from the top of eva orator 3 and a similar connection 8 leads tions 7 and 8 terminate in separable couplings or connections 7 and.8 respectively for convenient attachment to a pum or compressor such as 9, which, together w1th its operating motor 10, may be structurally united to form a small, compact, and light motor-pump unit, particularly when the pump is of the rotary type. Connection 7 is arranged to lead to the inlet of the ump and connection 8 to its outlet so that t e evaporator, pump and condenser are connected together to form a closed cycle system. Motor pump unit 10, 9 is shown disposed beneath the cabinet A, but it may be disposed at any other convenient oint. p The refrigerating plant is arranged to operate on the vapor-gas principle disclosed in my copending application Serial No. 15 172, filed March 12, 1925 and utilize a lubricating working substance such as disclosed in m copending application Serial No. 60,311 ed October 3, 1925 in accord- I ance with the processes disclosed in my coending applications Serial No. 85,580 filed ebruary 2, 1926 and Serial Nos. 196,825 and 106,826 filed Ma 5, 1926. A typlcal working substance 0 the described type 15 composed of methylene chloride 85% and a grease such as vaseline 15%. To properly concentrate such a working substance, the pump preferably operates at a fairly high temperature in order that the volatile component of the working substance may be driven oif. Hence, cooling of the pump is intentionally limited and no cooling means whatever are provided for it.

Condenser 4 is constructed and arranged to produce adequate cooling of the circulated working substance by natural draft. To this end condenser 4 is disposed in spaced relation to the wall of the cabinet and presents an extended surface as by the use of flattened or finned tubing which is found to give very satisfactory results with a column of air passing at low velocity such as is induced by vertically disposing the condenser and discharging the products of pump 9 at their greatest temperature into the top of the condenser. A considerable part of the heat is I found to dissipate by radiation while the refrom the top of condenser 4. Connecmainder of the heat which is given u passes. away by convection. The size of she a condenser is entirely practical and in most instances need not cover much more than a third of one side of the cabinet.

With no fan or other air agitating means needed to cool either condenser 4 or pump 6, it is obvious that there is no cooperation between the motor and the condenser or the pump for cooling pur oses. Hence, the motor-pump unit may at any convenient remote point from the other elements of the system. As this unit contains all the movmg parts of the system and the only ones or lnarily requlring servicing, the evaporator and condenser are built into and form a substantially permanent part of the refrigerator cabinet.

Since condenser 4 ives ofi much heat byradiation, it is desira le to deflect thesame away from cabinet A. This may be accomplished by making the insulated wall between the evaporator and the condenser of extra thickness or alternatively or additionally by providing intermediate the condenser and the wall a deflecting member which may take the form of a plate 11 which is spaced from both the wall and the condenser. This plate'may be of any suitable or desired material but since it is intended to deflect radiated heat it preferably is of some metal which presents a reflecting surface such, for example, as tin.

Suitable means are provided forprotecting the condenser element 4 against damage. 1 Such means may comprise side extensions a on cabinet A projecting beyond condenser 4, the the intervenin space between extensions 0. may be spanne by some form of suitable reticulated material 12, such as wire netting. 10

One or more bridge pieces 13 of metal or other suitable material may support the netting 12 intermediate extensions (1. I am aware that condensers have heretofore been incased to form so-called flues in order better to direct the cooling medium upon the condenser. N 0 such flue arrangement is required with my condenser which functions perfectly in the open air. The side extensions and the reticulated material are for protection onl and can be dispensed with entirely if not nee ed or desired so long as the atmosphere has free access to the condenser.

ile a preferred form of the invention has been herein shown and described, it is to be understood that the invention is not limited to the specific details thereof, but covers all changes, modifications, and adaptations within the scope of the appended claims.

I claim as my invention:

1. A refrligerator cabinet having an insulated wa an evaporator element upon one side of said well a condenser element upon the other side of said wall, and means interposed between said condenser element 130 and said wall for reflecting the heat of said last named element.

2. A refrigerator cabinet having an insulated wall, an evaporator element upon one side of said wall, a condenser element upon the other side of said wall, and a reflecting plate between said condenser element and said wall.

3. A refrigerator cabinet having an insulated wall, an evaporator element upon one side of said wall, a condenser element upon the other side of said wall, and a heat reflecting member between said condenser eleglellllt and said wall and in spaced relation to Signed by me at Detroit Wayne County,

Michigan, this 31st day of Jul 1926.

RANSOM W. DAVENPORT. 

